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1 Inflorescence branches flexuous, bractless or with a few very small bracts; heads 3-40 (-67) per plant; cypselas glabrous; plants with stems solitary or several from a crown, to 11 dm tall; [plants of upland dry to submesic habitats, typically glades, barrens, and dry to dry-mesic woodlands]
1 Inflorescence branches stiff, with numerous and well-developed bracts; heads (3-) 20-300+ per plant; cypselas glabrous to densely strigose; plants with stems scattered from creeping rhizomes (forming clonal patches), to 20 dm tall; [plants of wetland to mesic habitats, such as bogs, fens, seeps, wet meadows].
..2 Disk flowers 4-13 (-20) per head; ray flowers (2-) 3-avg. 4-5 (-7) per head; leaves mostly (1.5-) 2-3 (-4)× as long as wide, stiff, revolute; midveins of the phyllaries enlarged and translucent towards the tip; cypselas glabrate to sparsely strigose; [acid seepage in the Coastal Plain]
..2 Disk flowers (5-) 11-26 (-50) per head; ray flowers (2-) 5-avg. 8-12 (-16) per head; leaves (2-) 3.5-5 (-8)× as long as wide, flexible, planar; midveins of the phyllaries not swollen towards the tip; cypselas sparsely to moderately densely strigose; [widespread in our area]